• Journal of the Korean earth science society
• /
• v.33 no.6
• /
• pp.510-518
• /
• 2012

The Holocene climate change has been studied based on humus analysis of sediments that came from the Nam River basin in the Jinju, Gyeongnam. Humus and soil organic carbon analyses were performed to interpret the climate change and OSL dating and radiocarbon dating were conducted to determine the age of the sediments. The age determinations revealed that the sediments were formed approximately from $10,000{\pm}100$ yr. BP to $4,370{\pm}50$ yr. BP (2,970 BC) The deposits were classified into five layers based on sediments color and texture, and the climate change of each layer has been interpreted. The general climate was found out to be warm. The study result illustrated that section I was the lowest layer and section V the highest among the five surveyed sections. One the other hand, relatively cold events were detected in the sections ranging from I and II to III in terms of temperature. In term of humidity, sections II and III are estimated to have been relatively dry. Sections IV and V were relatively warm and dry, and the section IV tends to be warmest of the entire sedimentary. In addition, there is a tendency that the total soil organic carbon shows relatively high values under the cooler and humid climatic condition.

• Journal of Bio-Environment Control
• /
• v.20 no.3
• /
• pp.241-245
• /
• 2011

The study was conducted to evaluate the effects of organic materials commonly used for rice culture on the soil chemical properties and yield and quality of rice. Treatments were applied on the surface layer after rice planting and included: A) Kumsugangsangold, commonly used as a nutrient source for organic rice culture in Chonnam province (compost I), B) Rice bran, containing large quantities of vegetable ingredient (compost II), C) Chamdalkom, manufacturing by-product fish (compost III), and D) Hangawi, mixing anmimal and vegetable ingredients (compost IV). Seasonal N-mineralization rate was faster on the compost I and III with lower C:N ratio than those of the compost II and IV. Soil chemiceal properties were not significantly affected by treatments. Seasonal organic matter was higher on the compost II and IV with high input of the organic materials than those of compost I and III, which would affect the level of biomass C. Higher rice yield treated by compost I was observed in year 1, but no significant difference was observed in years 2 and 3.

• Journal of the Korean Wood Science and Technology
• /
• v.4 no.1
• /
• pp.38-47
• /
• 1976

This study was carried out to exploit and utilize American sycamore (Platanus occidentalis) and poplar grown in Korea as veneer species for plywood manufacture. At this study to save the imported lauan logs and dollars, the effects affecting to the properties of plywood constructed by sycamore, poplar and lauan veneers were studied. Important items dealt with this study were dry and wet shear strength, moisture content, and specific gravities By the results and discussion it may be summarized as followings. 1) Sycamore core lauan plywood (A-II type) was shown best dry shear strength, and the next were all lauan veneer plywood (A-I type), poplar core lauan plywood (B-I type), lauan core sycamore plywood (A-III type) in order. There are no differences between dry shear strength of A-II type and A-I type, A-II type and B-I type plywood. 2) Wet shear strength showed the same order with dry shear strength. A-II type plywood showed best wet shear strength and it showed more difference than other plwoods. A-I type, B-I type and A-III type plywood were all very good without significant difference in wet shear strength. 3) B-I type plywood showed highest moisture content of all type plywood and the next were all sycamore(A-IV type) all poplar plywood (B-III type), A-III type, B-II type, A-II type pllywood in order. Generally high moisture content showed when two or three veneers were same species in the three layer plywood. 4) A-III type plywood showed highest specific gravity of all and the next was A-IV type plywood without a difference to A-I type plywood on the whole. plywoods constructed by lauan and sycamore were shown high specific gravities and the next was lauan, sycamore and poplar, lauan and poplar. It seemed to be that connected wi th the specific gravity of veneer itself in different species. 5) The plywood manufactured by extension of potato flour is not only superior but also profitable in the price aspect than the plywood manufactured by extension of wheat flour.

• The korean journal of orthodontics
• /
• v.13 no.2
• /
• pp.155-163
• /
• 1983

Many different appliances have been used to move teeth or to attempt to inhibit or stimulate growth of the jaws. Especially, Orthopedic force was used to apply a constant force on the mandible. Various orthopedic forces bring the changes of surrounding tissue, growth and development on the mandibular joint. Author carried out this study to find the histological changes of the mandibular joint in rats when the mandible applied posterior displacement. For the purpose of this study, $009\times036inch$ closed coil spring and 030inch orthopedic wire were used between the post occipital region and the chin region in order to render the orthopedic forces, posteriorly. The experimental animals vu. used 1 month old (GroupI), 3 months old (Group II), and 12 months old (Group III) rats. Following results were obtained; 1. At the beginning of the experimental Group I, there were predominant increment of Cartilage layer in the posterior parts of condylar head. Especially, the mature chondrocyte zone was increased. 2. In the experimental Group II, the chondroblastic zone was decreased while it showed slightly increased mature cartilage zone. 3. In the experimental Group III, the mature chondrocyte zone was disappeared gradually and there was a tendency to reduce the endochondral bone formation in condylar head. 4. After 30 days of experimental Group I and in experimental Group II, there was a tendency to decrease the immature cellular zone in the glenoid fossa by pressure. 5. There were no histological changes in the articular disc by pressure.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.40 no.9
• /
• pp.1227-1234
• /
• 2011

We investigated the immunostimulatory effects of doenjang, a famous Korean traditional food made from fermented soybean paste, on the immunohistochemical reaction in the gastrointestinal (GI) tract and immune response in mice. Male C57BL/6N mice (6 weeks-old) were divided into 4 experimental diet treatment groups and a basal diet (control) group, and fed with different diets for 4 weeks. The immunoreactive density of $CD4^+/CD8^+$ lymphocytes were strongly stained in the jejunum and colon in Group III. The immunoreactivity of universal nitric oxide synthase (uNOS) was strongly stained in the myenteric plexus in the colon of all doenjang-fedgroups (I, II and III). The colonic immunoreactive density of protein kinase C-${\alpha}$ (PKC-${\alpha}$) was strongly increased in Groups II and III, while that of stem-cell factor (c-kit) was increased in colonic mucosa of all doenjang-fedgroups (I, II and III) and especially increased in the colonic muscle layer of Group III. These morphological and immunological results indicated that the intake of doenjang could improve the mucosal immune reaction, gastrointestinal motility, blood circulation in the GI tract, and the immuneactivity of the body. These results provide experimental evidence about the health benefits of doenjang.

• Journal of Chest Surgery
• /
• v.24 no.9
• /
• pp.837-842
• /
• 1991

Calcification is a major problem in glutaraldehyde-preserved bioprosthetic valves. We have used bovine pericardium processed in a solution containing 0.625% glutaraldehyde, 0.05M HEPES buffer and 0.26% magnesium chloride in saline. And, we also treated the glutaraldehyde-preserved bovine pericardium with a surfactant, Triton X - 100 to reduce calcification. To evaluate the degree of calcification. 4 kinds of pericardial xenografts, group I [Xenomedica, equine pericardial xenografts], group II [0.625% glutaraldehyde-preserved bovine pericardiums], group III [0.5% Triton X - 100 treated bovine pericardiums], and group IV [1.2% Triton X - 100 treated bovine pericardiums] were implanted in subcutaneous layer of growing rabbits, and they were explanted about 3 months later. The mean calcium contents[%/mg of dry tissue] of 0.5% and 1.2% Triton X - 100 treated bovine pericardiums [80.0$\pm$27.1%: 78.6$\pm$47.0% respectively] were lower than those of glutaraldehyde-preserved bovine pericardiums[126.2$\pm$29.8] [p=0.05]. Thus, under the conditions of subcutaneous implantation in rabbits, Triton X - 100 was efficient in calcification mitigation.

• Journal of Welding and Joining
• /
• v.18 no.4
• /
• pp.104-110
• /
• 2000

An integral equation representation of cracks was presented, which differs from well-known "dislocation layer" representation. In this new representation, an integral equation representation of cracks was developed and coupled to the direct boundary-element method for treatment of cracks in plane finite bodies. The method was developed for in-plane (modes I and II) loadings only. In this paper, the method is formulated and applied to mode III problems involving smooth or kinked cracks in finite region. The results are compared to exact solutions where available and the method is shown to be very accurate despite of its simplicity.implicity.

• Journal of the Korean Society for Industrial and Applied Mathematics
• /
• v.2 no.1
• /
• pp.111-129
• /
• 1998

An integral equation representation of cracks was presented, which differs from well-known "dislocation layer" representation. In this new representation, an integral equation representation of cracks was developed and coupled to the direct boundary-element method for treatment of cracks in plane finite bodies. The method was developed for in-plane(modes I and II) loadings only. In this paper, the method is formulated and applied to mode III problems involving smooth or kinked cracks in finite region. The results are compared to exact solutions where available and the method is shown to be very accurate despite of its simplicity.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2000.02a
• /
• pp.138-138
• /
• 2000

Kinetic behaviors of homoepitaxial growth on Ni(110) surface was studied at the growth-temperature ranges 290~380 K with scanning tunneling microscopy. At low temperature (~290 K), deposited Ni grows layer-by-layer mode in the first several layers with one-dimensional islands but eventually (at > monolayers) forms three-dimensional islands througy the kinetic shortening of the average length of one-dimensional islands. At the intermediat temperature (~340 K), the three-dimensional islands were observed to be I) regular mesa-like structure with high aspect ratio (~1:10) at ~15 monolayer, ii) hut-like structure with low aspect ratio (~1:1.5) at ~35 monolayer, and iii) rounded mound structure at ~55 monolayers, due to the competition of kinetic and energetic terms. At the high temperature (~ 380 K), the flat surface with layer-by-layer mode was observed up to 50 monolayers. Microscopic orgins for the observations will be discussed on the basis of kinetic Monte Carlo simulations.

• Advances in Traditional Medicine
• /
• v.10 no.1
• /
• pp.21-28
• /
• 2010

The objective of the present investigation is to evaluate the antimicrobial potency of the terpenoid fractions isolated from Luffa cylindrica seeds against various pathogenic microbes. The seeds were powdered and extracted with methanol in soxhlet appratus based on phytochemical screening. Three terpenoid components were isolated by column chromatography and identified by thin layer chromatography and chemical analysis which were designated as ${LCSF_4}^*$, ${LCSF_6}^*$ & ${LCSF_8}^*$ respectively. Disc diffusion method was employed to determine the antimicrobial effectiveness of test compounds I, II and III $({LCSF_4}^*,\;{LCSF_6}^*\;&\;{LCSF_8}^*)$ against 6 microbial species viz., Staphylococcus (S.) aureus, Bacillus (B.) subtilis, Escherichia (E.) coli, Pseudomonas (P.) aeruginosa, Candida (C.) albicans and Aspergillus niger. The disc was saturated with $100{\mu}l$ of each compound, allowed to dry and introduced on the upper layer of seeded agar plate. The plates were incubated overnight at $37^{\circ}C$. Microbial growth was determined by measuring the zonal inhibition diameters. Compound I showed maximum potency against gram positive S. aureus (21 mm) in comparison with standard ciprofloxacin (38 mm), whereas the same compound was completely devoid of activity against both the fungi tested. Compound II was found to be highly sensitive against both the gram negative E. coli (20 mm) and P. aeruginosa (22 mm). Compound II was found to exhibit maximum potency against the fungi C. albicans (15 mm) and A. niger (20 mm). Compound III was found to be very effective against both the gram positive S. aureus (20 mm) and B. subtilis (15 mm) respectively.